This “people detector” with pyroelectric sensor was found in the April 1991 issue of Radio Electronics magazine. The circuit is based on an LM324 and a sensor from that time.
What is a dual frequency generator for? There are several possibilities of use for this circuit. The...
The circuit, illustrated in the figure, consists of the direct application of the ULN2003 in which...
This circuit was found in a Popular Electronics from the 90's. The output signal can be applied to a...